LibGdx，视口/相机#unProject有时（并非总是）返回错误的值

Question

我使用OrthographicCamera和unproject函数将屏幕点转换为世界点。

一切正常，但是有时#unproject方法返回一些几乎是好的/期望值，但是几乎是，因此您在屏幕/世界跳跃X像素/单位时会看到它。

//screenX, screenY -> mouse position when wheel is scrolled

(...) <- calculate new world size because of zooming and set it up in viewport object

//calculate difference in world two points
//where mouse was before zooming and where mouse is after it,
//related to worldCoords, and apply it to camera:
Vector2 before = viewport.unproject(new Vector2(screenX, screenY));
camera.viewportWidth = viewport.getWorldWidth();
camera.viewportHeight = viewport.getWorldHeight();
camera.update();
Vector2 after = viewport.unproject(new Vector2(screenX, screenY));
camera.position.x -= after.x - before.x;
camera.position.y -= after.y - before.y;

此代码仅将重点放在“世界中的点”功能上-进行缩放

编辑/解决方案？ ：

OrthographicCamera类中的方法更新：

@Override
    public void update (boolean updateFrustum) {
        projection.setToOrtho(zoom * -viewportWidth / 2, zoom * (viewportWidth / 2), zoom * -(viewportHeight / 2), zoom
            * viewportHeight / 2, near, far);
        view.setToLookAt(position, tmp.set(position).add(direction), up);
        combined.set(projection);
        Matrix4.mul(combined.val, view.val);

        if (updateFrustum) {
            invProjectionView.set(combined);
            Matrix4.inv(invProjectionView.val);
            frustum.update(invProjectionView);
        }
    }

看起来这行是有罪的：

view.setToLookAt(position, tmp.set(position).add(direction), up);

您可以复制此方法的代码并创建自己的方法，而无需使用它。 我猜这种方法只是个小虫子，很难找到。 现在，其他人必须更深入并在setToLookAt中找到真正的原因。